Birmingham | ITP-Jan-26 | Ayodeji Ayorinde | Sprint 3| practice-tdd

Sprint-3/2-practice-tdd/count.js

@@ -1,5 +1,21 @@
-function countChar(stringOfCharacters, findCharacter) {
-  return 5
+
+
+/**
+ * Counts the occurrences of a character within a string.
+ * @param {string} str - The string to search through.
+ * @param {string} char - The character to look for.
+ * @returns {number} - The total count of the character.
+ */
+function countChar(str, char) {
+  let count = 0;
+
+  for (const letter of str) {
+    if (letter === char) {
+      count++;
+    }
+  }
+
+  return count;
 }
 
-module.exports = countChar;
+module.exports = countChar;

Sprint-3/2-practice-tdd/count.test.js

@@ -1,5 +1,10 @@
 // implement a function countChar that counts the number of times a character occurs in a string
+
+/*
 const countChar = require("./count");
+*/
+
+
 // Given a string `str` and a single character `char` to search for,
 // When the countChar function is called with these inputs,
 // Then it should:
@@ -10,15 +15,47 @@ const countChar = require("./count");
 // When the function is called with these inputs,
 // Then it should correctly count occurrences of `char`.
 
+/*
 test("should count multiple occurrences of a character", () => {
   const str = "aaaaa";
   const char = "a";
   const count = countChar(str, char);
   expect(count).toEqual(5);
 });
+*/
 
 // Scenario: No Occurrences
 // Given the input string `str`,
 // And a character `char` that does not exist within `str`.
 // When the function is called with these inputs,
 // Then it should return 0, indicating that no occurrences of `char` were found.
+
+
+
+const countChar = require("./count");
+
+describe("countChar function", () => {
+  // Scenario: Multiple Occurrences
+  test("should count multiple occurrences of a character", () => {
+    const str = "aaaaa";
+    const char = "a";
+    const count = countChar(str, char);
+    expect(count).toEqual(5);
+  });
+
+  // Scenario: No Occurrences
+  test("should return 0 when the character does not exist in the string", () => {
+    const str = "hello";
+    const char = "z";
+    const count = countChar(str, char);
+    expect(count).toEqual(0);
+  });
+
+  // Bonus Scenario: Mixed Case (Character searching is case-sensitive)
+  test("should be case-sensitive", () => {
+    const str = "Abba";
+    const char = "a";
+    const count = countChar(str, char);
+    expect(count).toEqual(1); // Only the lowercase 'a' is counted
+  });
+});

Sprint-3/2-practice-tdd/get-ordinal-number.js

@@ -1,5 +1,29 @@
+
+
 function getOrdinalNumber(num) {
-  return "1st";
+  const s = num.toString();
+  const lastDigit = num % 10;
+  const lastTwoDigits = num % 100;
+
+  // Rule for 11th, 12th, 13th (The "Teens" exception)
+  if (lastTwoDigits >= 11 && lastTwoDigits <= 13) {
+    return s + "th";
+  }
+
+  // Standard rules based on the last digit
+  switch (lastDigit) {
+    case 1:
+      return s + "st";
+    case 2:
+      return s + "nd";
+    case 3:
+      return s + "rd";
+    default:
+      return s + "th";
+  }
 }
 
+
 module.exports = getOrdinalNumber;
+
+

Sprint-3/2-practice-tdd/get-ordinal-number.test.js

@@ -1,20 +1,42 @@
+
 const getOrdinalNumber = require("./get-ordinal-number");
-// In this week's prep, we started implementing getOrdinalNumber.
 
-// Continue testing and implementing getOrdinalNumber for additional cases.
-// Write your tests using Jest — remember to run your tests often for continual feedback.
+describe("getOrdinalNumber", () => {
+  // Case 1: Numbers ending with 1 (but not 11)
+  test("should append 'st' for numbers ending with 1, except those ending with 11", () => {
+    expect(getOrdinalNumber(1)).toBe("1st");
+    expect(getOrdinalNumber(21)).toBe("21st");
+    expect(getOrdinalNumber(101)).toBe("101st");
+  });
+
+  // Case 2: Numbers ending with 2 (but not 12)
+  test("should append 'nd' for numbers ending with 2, except those ending with 12", () => {
+    expect(getOrdinalNumber(2)).toBe("2nd");
+    expect(getOrdinalNumber(42)).toBe("42nd");
+    expect(getOrdinalNumber(122)).toBe("122nd");
+  });
+
+  // Case 3: Numbers ending with 3 (but not 13)
+  test("should append 'rd' for numbers ending with 3, except those ending with 13", () => {
+    expect(getOrdinalNumber(3)).toBe("3rd");
+    expect(getOrdinalNumber(53)).toBe("53rd");
+    expect(getOrdinalNumber(1003)).toBe("1003rd");
+  });
 
-// To ensure thorough testing, we need broad scenarios that cover all possible cases.
-// Listing individual values, however, can quickly lead to an unmanageable number of test cases.
-// Instead of writing tests for individual numbers, consider grouping all possible input values
-// into meaningful categories. Then, select representative samples from each category to test.
-// This approach improves coverage and makes our tests easier to maintain.
+  // Case 4: The Teen Exceptions (11, 12, 13)
+  test("should append 'th' for numbers ending in 11, 12, or 13", () => {
+    expect(getOrdinalNumber(11)).toBe("11th");
+    expect(getOrdinalNumber(12)).toBe("12th");
+    expect(getOrdinalNumber(13)).toBe("13th");
+    expect(getOrdinalNumber(111)).toBe("111th"); // Edge case: triple digits
+  });
 
-// Case 1: Numbers ending with 1 (but not 11)
-// When the number ends with 1, except those ending with 11,
-// Then the function should return a string by appending "st" to the number.
-test("should append 'st' for numbers ending with 1, except those ending with 11", () => {
-  expect(getOrdinalNumber(1)).toEqual("1st");
-  expect(getOrdinalNumber(21)).toEqual("21st");
-  expect(getOrdinalNumber(131)).toEqual("131st");
+  // Case 5: All other numbers (Ending in 0, 4, 5, 6, 7, 8, 9)
+  test("should append 'th' for all other numbers", () => {
+    expect(getOrdinalNumber(0)).toBe("0th");
+    expect(getOrdinalNumber(4)).toBe("4th");
+    expect(getOrdinalNumber(9)).toBe("9th");
+    expect(getOrdinalNumber(10)).toBe("10th");
+    expect(getOrdinalNumber(20)).toBe("20th");
+  });
 });

Sprint-3/2-practice-tdd/repeat-str.js

@@ -1,5 +1,20 @@
-function repeatStr() {
-  return "hellohellohello";
+
+
+/**
+ * Repeats a string a given number of times.
+ * @param {string} str - The string to repeat.
+ * @param {number} count - The number of times to repeat the string.
+ * @returns {string} - The repeated string.
+ * @throws {Error} - If count is a negative integer.
+ */
+function repeatStr(str, count) {
+  if (count < 0) {
+    throw new Error("Count must be a non-negative integer");
+  }
+
+  // If count is 0, .repeat(0) naturally returns an empty string "".
+  // If count is 1, .repeat(1) naturally returns the original string.
+  return str.repeat(count);
 }
 
 module.exports = repeatStr;

Sprint-3/2-practice-tdd/repeat-str.test.js

@@ -1,5 +1,48 @@
+
+const repeatStr = require("./repeat-str");
+
+describe("repeatStr", () => {
+  // Case: handle multiple repetitions
+  test("should repeat the string count times", () => {
+    const str = "hello";
+    const count = 3;
+    const repeatedStr = repeatStr(str, count);
+    expect(repeatedStr).toEqual("hellohellohello");
+  });
+
+  // Case: handle count of 1
+  test("should return the original string when count is 1", () => {
+    const str = "apple";
+    const count = 1;
+    expect(repeatStr(str, count)).toEqual("apple");
+  });
+
+  // Case: Handle count of 0
+  test("should return an empty string when count is 0", () => {
+    const str = "ghost";
+    const count = 0;
+    expect(repeatStr(str, count)).toEqual("");
+  });
+
+  // Case: Handle negative count
+  test("should throw an error when count is negative", () => {
+    const str = "error";
+    const count = -1;
+
+    // We wrap the call in a function so Jest can catch the error
+    expect(() => {
+      repeatStr(str, count);
+    }).toThrow("Count must be a non-negative integer");
+  });
+});
+
+
 // Implement a function repeatStr
+
+/*
 const repeatStr = require("./repeat-str");
+*/
+
 // Given a target string `str` and a positive integer `count`,
 // When the repeatStr function is called with these inputs,
 // Then it should:
@@ -9,13 +52,17 @@ const repeatStr = require("./repeat-str");
 // When the repeatStr function is called with these inputs,
 // Then it should return a string that contains the original `str` repeated `count` times.
 
+/*
 test("should repeat the string count times", () => {
   const str = "hello";
   const count = 3;
   const repeatedStr = repeatStr(str, count);
   expect(repeatedStr).toEqual("hellohellohello");
 });
 
+*/
+
+
 // Case: handle count of 1:
 // Given a target string `str` and a `count` equal to 1,
 // When the repeatStr function is called with these inputs,